Outside a home, there is a 10- key pad with letters a, b, c,d, e,f, g,h, i and j that can be used to open a garage door if the correct ten letter code s entered each key can only be used once. how many codes are there?

There are 3,628,800 possible codes.

Step-by-step explanation:

Observe that:

Following this argument we can see that the number of possible choices for the 4th,5th,6th,7th,8th,9th and 10th letter are 7,6,5,4,3,2 and 1 respectively.

Finally, since the letters choice are independent, we have that the number of possible codes is given by

(1, –1), (16, –4), (36, –6)

step-by-step explanation:

given that the function is

this can also be written as

we have to graph this function and check which list of points lie on the graph

see attachment for graph:

we find that the points lying are (1,-1) (16,-4) and (36,-6)

since square root is there we find that x can only be posiitve but y can be since square root both positive and negative.